Dolferus R, Jacobs M, Peacock W J, Dennis E S
Commonwealth Scientific and Industrial Research Organization, Division of Plant Industry, Canberra, Australia.
Plant Physiol. 1994 Aug;105(4):1075-87. doi: 10.1104/pp.105.4.1075.
The Adh (alcohol dehydrogenase, EC 1.1.1.1.) gene from Arabidopsis thaliana (L.) Heynh. can be induced by dehydration and cold, as well as by hypoxia. A 1-kb promoter fragment (CADH: -964 to +53) is sufficient to confer the stress induction and tissue-specific developmental expression characteristics of the Adh gene to a beta-glucuronidase reporter gene. Deletion mapping of the 5' end and site-specific mutagenesis identified four regions of the promoter essential for expression under the three stress conditions. Some sequence elements are important for response to all three stress treatments, whereas others are stress specific. The most critical region essential for expression of the Arabidopsis Adh promoter under all three environmental stresses (region IV: -172 to -141) contains sequences homologous to the GT motif (-160 to -152) and the GC motif (-147 to -144) of the maize Adh1 anaerobic responsive element. Region III (-235 to -172) contains two regions shown by R.J. Ferl and B.H. Laughner ([1989] Plant Mol Biol 12: 357-366) to bind regulatory proteins; mutation of the G-box-1 region (5'-CCACGTGG-3', -216 to -209) does not affect expression under uninduced or hypoxic conditions, but significantly reduces induction by cold stress and, to a lesser extent, by dehydration stress. Mutation of the other G-box-like sequence (G-box-2: 5'-CCAAGTGG-3', -193 to -182) does not change hypoxic response and affects cold and dehydration stress only slightly. G-box-2 mutations also promote high levels of expression under uninduced conditions. Deletion of region I (-964 to -510) results in increased expression under uninduced and all stress conditions, suggesting that this region contains a repressor binding site. Region II (-510 to -384) contains a positive regulatory element and is necessary for high expression levels under all treatments.
拟南芥（Arabidopsis thaliana (L.) Heynh.）的乙醇脱氢酶（Adh，酒精脱氢酶，EC 1.1.1.1.）基因可被脱水、低温以及缺氧诱导。一个1千碱基对的启动子片段（CADH：-964至+53）足以将Adh基因的胁迫诱导和组织特异性发育表达特征赋予β-葡萄糖醛酸酶报告基因。对5'端进行缺失作图和位点特异性诱变确定了启动子在三种胁迫条件下表达所必需的四个区域。一些序列元件对所有三种胁迫处理的响应都很重要，而其他元件则具有胁迫特异性。在所有三种环境胁迫下，拟南芥Adh启动子表达所必需的最关键区域（区域IV：-172至-141）包含与玉米Adh1厌氧响应元件的GT基序（-160至-152）和GC基序（-147至-144）同源的序列。区域III（-235至-172）包含两个被R.J.费尔和B.H.劳夫纳（[1989]《植物分子生物学》12：357 - 366）证明能结合调节蛋白的区域；G-box-1区域（5'-CCACGTGG-3'，-216至-209）的突变在未诱导或缺氧条件下不影响表达，但显著降低了低温胁迫诱导，在较小程度上也降低了脱水胁迫诱导。另一个G-box样序列（G-box-2：5'-CCAAGTGG-3'，-193至-182）的突变不改变缺氧响应，对低温和脱水胁迫的影响也很小。G-box-2突变还会在未诱导条件下促进高水平表达。区域I（-964至-510）的缺失导致在未诱导和所有胁迫条件下表达增加，表明该区域包含一个阻遏物结合位点。区域II（-510至-384）包含一个正调控元件，是所有处理下高表达水平所必需的。
